JPS5899575A - Valve - Google Patents

Abstract

PURPOSE:To simplify the structure and obtain the quick response of a valve by shifting an opposing point between an operation spring made of shape-memorizing alloy and a bias spring opposite thereto for moving a needle to control discharge. CONSTITUTION:For example, in the case of an expansion valve, a valve body 7 is connected to refrigerating cycle via pipe 8 and 9, and the position of a needle 10 is maintained by a balancing power between an operation spring 13 made of shape-memorizing alloy and an opposing bias spring 12. Current can be supplied to the operation spring 13 from electrodes 16 and 17 via lead wires 18 and 19. When the current is supplied to the operation spring 13, the spring is shrinked, and the needle 10 is moved oppositely to the illustration of an arrow to increase the passing amount of refrigerant. This construction permits to regulate the gap between the needle 10 and a needle receiver 11 in accordance with the passing amount of the current.

Description

[Detailed Description of the Invention] The present invention relates to an improvement in the structure of a valve such as an expansion valve or an on-off valve provided in a refrigeration cycle, and particularly relates to a structure in which an operating spring is formed of a shape memory alloy. In alloys of is known to have. Due to this unique property, even if it is deformed by a certain stress below the martensitic transformation temperature, if it is heated to above the martensitic transformation temperature under zero stress, it will retain the shape that was heat treated under certain conditions. In addition, there is superelasticity due to stress-induced martensite, which occurs when stress is applied even above the martensitic transformation temperature, and these can occur in a narrow temperature range of several tens of degrees Celsius. . When the stress-induced martensitic phase, which is stable at a temperature equal to or higher than the martensitic transformation temperature under a certain stress, is further heated, it overcomes the stress and transforms back into the parent phase. At this time, the force generated in this alloy is much greater than the force required to form and deform martensite. Therefore, a difference in temperature (2) degrees can be converted into a difference in force and can be used as a driving source. The martensitic transformation temperature and the degree of stress required to produce stress-induced martensite vary depending on the type of alloy, composition, manufacturing method, heat treatment conditions, and shape of the alloy, and are unique to each alloy. In addition, the martensite transformation temperature and the temperature range where stress-induced martensite occurs is several tens of degrees Celsius.
There are various types of alloys that have a temperature range near normal temperature.Therefore, by using these alloys (hereinafter referred to as shape memory alloys), one driving source can be obtained. The invention was developed by focusing on this point, and in a valve equipped with an operating spring and a bias spring installed opposite to the operating spring, the operating spring is formed of a shape memory alloy, and the operating spring and the bias spring are The present invention provides a valve whose special purpose is to control the flow rate of fluid by moving a needle by moving the opposite point of the valve.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cycle diagram of a refrigeration cycle using the valve according to the present invention, and FIG. 2 is a sectional view showing the structure of the valve according to the present invention.

First, to explain Fig. 1, ■ is the refrigerant compressor, 2 is the refrigerant compressor,
3 is an expansion valve having a valve structure according to the present invention; 4 is a condenser;
is an evaporator, and 5 and 6 are blowers.

In the refrigeration cycle shown in FIG. 1, high-temperature refrigerant gas discharged from the compressor 1 enters the condenser 2, is cooled and condensed by the air blown by the blower 5, and is then depressurized by the expansion valve 3.
It enters the evaporator 4, is evaporated by the air blowing from the blower 6, returns to the compressor 1, is compressed, and repeats this cycle thereafter.

Next, the expansion valve 3 having the valve structure according to the present invention will be explained with reference to FIG. 2. First, 7 is the valve body, 8°9 is a pipe connected to the refrigeration cycle, 10il-1 is a needle, 11
12 is a bias spring; 13 is an operating spring made of the aforementioned shape memory alloy; and is insulated from the valve body 7 by insulators 14 and 15. I6 and 17 are electrodes for passing current through the operating spring 13, and are insulated from the valve body 7 by glass seals +6a, +7a, etc., and are connected to the operating spring 13 through lead wires 18 and 19, respectively.

The operating spring 13 expands when not energized and moves in the direction of contracting to its original shape when energized. Therefore, by increasing the amount of energization, the needle 10 moves in the opposite direction to the arrow, and the needle 10 and needle receiver 12 By increasing the gap between the two needles and increasing the amount of refrigerant passing through, and conversely reducing the amount of current, the needle IO moves in the direction of the arrow and can reduce the amount of refrigerant passing through.

Conventional expansion valves of this type generally use a bimetal and a heater, but they are made up of a heating element (heater) and an operating element (bimetal), as follows: heater overheating → heat conduction → bimetal → operation. Therefore, insulation was required between them, and the structure was complicated.

In the present invention, as described above, the heating element and the operating element are both used, so the structure is simple and the response is quick.

In the structure shown in FIG. 2, the valve operates in the opening direction when energized, but if the operating spring 13 and bias spring 12 are reversed, the valve can also be operated in the closing direction when energized.

As an application of the present invention, not as an expansion valve but as a normal valve,
It can also be used as a delayed action motor-operated valve that is normally closed and opens when energized, and normally open and closes when energized.

In addition to controlling the opening degree by applying electricity, the opening degree can also be controlled by the temperature of the passing refrigerant.

For example, in the structure shown in FIG. 2, even if no electricity is applied, it opens when refrigerant of 50° C. flows, and closes when low-temperature refrigerant flows.

As described above, according to the present invention, an element corresponding to a conventional heating element and an operating element are combined, so that the structure is simpler than that of the conventional one, and the response is faster.

[Brief explanation of drawings]

FIG. 1 is a cycle diagram of a refrigeration cycle using the valve according to the present invention, and FIG. 2 is a sectional view showing the structure of the valve according to the present invention. 7: Valve body, 10: Needle, 12: Bias spring, 1
3: Operation spring. Agent Patent Attorney Aihiko Fuku t7) Kaya Figure 1 Figure 2

Claims (1)

[Scope of Claims] (1) In a valve equipped with an operating spring and a bias spring installed opposite to the operating spring, the operating spring is formed of a shape memory alloy, and the opposing point between the operating spring and the bias spring is A valve characterized by controlling the flow rate of fluid by moving a needle. 2. Claim 1, characterized in that the motion of a motion spring formed of a shape memory alloy is controlled by energization.
Valve as described in section. 3. The valve according to claim 1, wherein the operation of the operating spring made of a shape memory alloy is controlled by the temperature of the fluid itself.